package com.baoming.util;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;

import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@SuppressWarnings("serial")
public class MemberLoginPageCode extends HttpServlet {
	  
	private  Color getRandColor(int fc, int bc) { 
		Random random = new Random();
		if (fc > 255)
			fc = 255;
		if (bc > 255)
			bc = 255;
		int r = fc + random.nextInt(bc - fc);
		int g = fc + random.nextInt(bc - fc);
		int b = fc + random.nextInt(bc - fc);
		return new Color(r, g, b);
	}
	
	private String getCodeStr(){
		Random random = new Random();
		String sRand = "";
		for (int i = 0; i < 4; i++) {
			String rand = String.valueOf(random.nextInt(10));
			sRand += rand;
		}
		return sRand ; 
	}
	
	private BufferedImage craeteImg(String sRand){
		Random random = new Random(); 
		int width = 55;
		int height = 30;
		BufferedImage image = new BufferedImage(width, height,
				BufferedImage.TYPE_INT_RGB);
		Graphics g = image.getGraphics();
 
		g.setColor(getRandColor(200, 250));
		g.fillRect(0, 0, width, height);
		g.setFont(new Font("serif", Font.CENTER_BASELINE, 16));
		g.setColor(getRandColor(160, 200));
		for (int i = 0; i < 100; i++) {
			int x = random.nextInt(width);
			int y = random.nextInt(height);
			int xl = random.nextInt(12);
			int yl = random.nextInt(12);
			g.drawLine(x, y, x + xl, y + yl);
		}
		
		for (int i = 0; i < 4; i++) {
			String rand = sRand.substring(i, i + 1);  
			g.setColor(new Color(20 + random.nextInt(110), 20 + random
					.nextInt(110), 20 + random.nextInt(110))); 
			g.drawString(rand, 13 * i + 6, 20);
		}
		g.dispose();
		
		return image ; 
	}
	
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		response.setHeader("Pragma", "No-cache");
		response.setHeader("Cache-Control", "no-cache");
		response.setDateHeader("Expires", 0);
		
		String rStr = getCodeStr() ; 
		request.getSession().setAttribute("LOGIN_CHECK_NUMBER_KEY", rStr);
		BufferedImage image = craeteImg(rStr) ; 
		try {
			ImageIO.write(image, "JPEG", response.getOutputStream());
		} catch (Exception e) {
			e.printStackTrace() ; 
		} 
	}

 
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		this.doGet(request, response) ; 
	}

}
